Refrigeration



April 7, 1942. A. R. THOMAS REFRIGERATION Filed June 28, 1940 ATTORNEY embedded in aheat insulating material ll.

Patented Apr. 7, 1942 Albert R. Thomas, Evansville, Ind., assignor Servel, Inc., New York, M11, a corporation of I Delaware Application June 28, 1940, Serial No. 342,a91

6 Claims. (01. 62-125) This invention relates to refrigeration, and more particularly to a system .for transferring heat so that cooling may be produced at a place above a source of refrigeration.

It is an object of the invention to provide a simple arrangement for elevating liquid heat transfer fluid in such a system: In the drawing: Fig. 1 illustrates diagrammatically a refrigerating system embodying my invention; and

Fig. 2 is an enlarged view, partly in vertical section, of the lower part of the system shown in Fig. 1.

In Fig. lther'e is shown a cooling unit or evaporator I of a refrigeration apparatus of a, uniform pressure absorption type like that described in my Patent No. 2,207,838, granted July 14, 1940. The cooling unit It constitutes a source of, refrigeration and comprises an outershell which is A liquid refrigerant, such as ammonia, is introduced into the upper part of the cooling unit Ill through a conduit l2. An inert gas, such as hydrogen, enters the upper part of the cooling unit from the upper end of a cylinder I3 disposed within the shell. The liquid ammonia evaporates and difiuses into the-hydrogen with consequent absorption of heat from the surroundings to produce a refrigerating effect. This refrigerating effect is utilized to cool and liquefy a volatile fluid flowing through a coil M which is arranged about the cylinder l3 and over the successive turns of which the liquid ammonia descends in sheetlike form.

r The resulting gas mixture of ammonia and hydrogen flows from the cooling unit ID to an absorber in which the ammonia is absorbed into a liquid absorbent such as water. The inert hydrogen gas is returned to the cylinder l3 and the enriched absorption liquid is conducted to a generator. By heating the generator, the ammonia is expelled from the absorption solution, liquefled in a condenser and then returned to the cooling unit l0 through conduit l2 to complete the refrigerating cycle. The weakened absorption solution from which the ammonia has been expelled is conducted from the generator to the absorber to absorb ammonia gas. In order to simplify the drawing, the absorber, generator and condenser of the refrigeration apparatus associated with the cooling unit ill have not been shown, their illustration not being necessary for an understanding of my invention.

The coil [4 which is arranged within and in thermal relation with the cooling unit III of the refrigeration apparatus just described, constitutes the condenser-of a heat transfer system. The condenser I4 is disposed below an evaporator ii of the flooded type which is located in a'thermally insulated storage space l6 that is to be maintained at adesired low temperature. The evaporator l5 includesa receiver I!- and a looped coil 18 which is provided with heat transfer flns l9 and connected to the receiver I1. I

The condenser I4 and evaporator I5 form part of a closed fluid circuit which contains a suitable volatile fluid such as methyl chloride or freon that evaporates within the evaporator l5 and takes up heat thereby producing cold. The vapor flows from the evaporator l5 through a conduit 20 into the condenser l4, and the vapor is'cooled and condensed by the cooling unit It.

Since the condenser I4 is disposed at a lower level than the evaporator I 5; means is provided to return the liquid to the evaporator so-that cooling may be constantly produced in the storage space Hi. This means comprises a vessel'2l which is joined to the bottom of coil I4 by a pipe 22. The open end of pipe 22 projects downward in vessel 2|. A pipe 23 connects the'bottom of vessel 2| to the lower part of a vessel 24; A check valve 25 is provided in pipe 23 to allow flow of liquid from pipe 23 to vessel 24 but prevent flow in the reverse direction.

A pipe 26 connects the top of vessel 24 with the top of a coil 21 located in vessel 2| and surrounding pipe 22. The bottom of coil 21 is connected by a pipe 28 to a vessel 29. This vessel may be heated in any convenient manner as by atmosphere, by waste heat, or by-a heater, representatively shown as a burner 3|]. The other parts which have been described are enclosed in thermal insulation, not only shown for clarity.

The bottom of vessel 24 is connected by an insulated pipe 3| with the receiver l'l in storage space IS. The operation of the liquidtransfer device of. this invention is as follows:

Condensed heat transfer fluid flows from coil 14 down pipe 22 into vessel 2|. The liquid fills pipe 23 and the vessel or jacket. 21 around coil 24. When suflicient pressure is generated in said vessel, the liquid is forced up through pipe 3| into receiver" II. The check valve 2| cooling condensed liquid, and utilizing the subprevents the liquid from being forced back through pipe 23. 1

Various changes and modifications may be made within the'scope of the invention as set forth in the following claims. g Whatisclaimedis: a 5

i 1. Refrigeration apparatus including a cooling element anda circuit for volatile heat transfer fluid having a condenser in heat transfer relation with said cooling element, an evaporaton-lov cooled liquid to intermittently decrease the pressure of said vapor, and forming a body of liquid pressure to be condensate upon said decrease in raised upon increase thereof.

5. Refrigeration apparatus including a cooling element and a circuit for volatile heattransfer fluid having a condenser inmheat transier relation with, said; cooling element, an evaporator located at a level above said condenser, a-chamher in said circuit connected for inflow of liquid condensate from said condenser and outflow thereof'to said evaporator. a second condenser cated at a level above said condenser, a chamber in said circuit connected for inflow of liquid 'c6n-' densate from said condenser and outflow'thereof to said evaporator, and means operated by subcooling of liquid condensate insaid-condenser to produce intermittentydecrease in pressure of vapor in said chamber to cause said inflow of which takes place when thepressure resumes.

2.. Refrigeration apparatus as set forth in claim 1 in which saidmeans comprisesa second -condenser connected to said chamber-and arranged connected to the upper part of said chamber, a

heat receiving vessel connected to said second condenser and arrangedso that liquid formed in said second condenser flows into said vessel, said second condenserbeing so arranged as to be in contact with liquid in a path of flow fromsaid 'liquideondensate alternately with said outflow in heat transfer-relation with liquid, condensate i in,,a pathbf flow from said first condensergto, said chamber. r i v I 3. Refrigeration..apparatus as set forth in claim l injw'hich saidchamber is thermally including a heated vessel connected; to the V l upper part of saidch amher, and in which said means comprises} second condenser connected,

to said vesseland arranged'in heat transfer rela- -.tion. with liquid condensate in apath lof flowu from said first condenser to said chamber;

U 4. A method of cooling which includes ,slm'ultaneousiy vaporizing-liquid fluid at anmmwnelevation, condensing vaporized fluid to liquid at-a lower elevation, maintaining vapor under pressurein direct contact with said condensed liquid to raise the, li qllid;lbetween, said levations, sub-' element. and a circuit for volatile heat first condenser to said chamber only when said path of flow is flooded with liquid. l e

- 6. Refrigeration apparatus including fluid having a condenser in heat transfer-relation with said cooling element, an evaporator lo-* eated at a level-above said condenser, atliquid transfer chamber, a conduitfor liquidfrom the lower-part ofsaid chamber to said evaporator,

asecond condenser connected to the upper part of said-chamber, a heat receiving vessel connected to said condenser and arrangedi totreceive condensate formed in said second condenser,

a conduit for vapor from said, evaporatonto said first jcondenser, a vesselcencloslng, said1 second condenser, a conduitfromsaid first condenser to .thelower partof said last, vessel, aconduitfrom "thelower of said last vessel to the lower part of said transfer chamber, and means insaid 118st conduit for permitting n w of liquidoniy in thedirection of said chamber. I

- V ALBERT RbTHOMAS-q transfer 

